A long time I ago I "automated" the optimization of images on my site by running `optipng` in a cronjob. Every file that touches my server gets optimized.
I wrote about it here: https://ma.ttias.be/optimize-size-png-images-automatically-w...
Benefits:
- Don't have to think about it
- Optipng is really good at reducing PNG's to their bear minimum
Downsides:
- Doesn't resize images (if a 1024x768 is displayed as a 10x8, it'll still download the 1024x768)
- Only does PNG
- If your images are stored in git (and you didn't pre-optimize before committing/deploy), you can get merge conflicts
Still, better than nothing.